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Abstract: An ultrasound-enhanced five-stage gradient elution system employing mixed solutions of Triton X-100 (TX100), sodium dodecyl benzenesulfonate (SBDS), and salt (abbr. MSTS) was used to elute super heavy oil from weathered soils. The use of ultrasound increased the elution of super heavy oil by 13–14% and improved first-stage dissolution and dispersion by 62%. However, the amount of super heavy oil dissolved or dispersed in the second through fifth elution stages was unchanged by the application of ultrasound. Saturated hydrocarbons were more quickly eluted in the first two stages. During the final three stages the order of elution for the four identified super heavy oil fractions was: asphaltenes>saturated hydrocarbons>aromatics>resins. A large number of elution stages aided in eluting markers containing a large number of C atoms in the absence of ultrasound. The elution at each stage was higher when ultrasound was employed, and ultrasound-enhanced elution is a potentially useful method for removing super heavy oil from weathered soils. [ABSTRACT FROM AUTHOR]

Bacterial communities, taxonomic functional groups, and chemical characteristics of granular sludge were assessed in an ultrahigh-temperature (70°C) upflow anaerobic sludge blanket reactor (UASB) used to treat super heavy oil-containing wastewater. The UASB, with an organic loading rate of 3.0 kg COD m−3 day−1, achieved an average chemical oxygen demand removal of 48%, with 52% oil removal from the wastewater. It was also found to successfully degrade two typical biomarkers of super heavy oil, C26-34 17α 25-norhopanes and C26-28 triaromatic steroid. Scanning electron microscope, Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction results showed that the granular sludge became more compact with an increased quantity of extracellular polymeric substances, Fe2O3, FeS, and CaCO3 crystals in the reactor. Polymerase chain reaction-denaturing gradient gel electrophoresis and real-time polymerase chain reaction results indicated that after 90 days of operation, the density of total bacteria in the UASB dropped while Pseudomonas density increased, making it a dominant bacterium in the reactor. Data obtained from this research will provide useful information and insights with respect to effective treatment for super heavy oil wastewater under ultrahigh-temperature conditions. [ABSTRACT FROM AUTHOR]

Abstract: An ultrasound-enhanced elution system with Triton X-100 solution was used to remediate aging soils contaminated with super heavy oil. We used GC/MS, SEM, and X-ray diffraction (XRD) to analyze the effect of ultrasonic time (0–1800s) on the elution of super heavy oil and its three characteristic biomarkers (C26–34 17α 25-norhopanes, C26–28 triaromatic steroid [TAS], and C27–29 methyl triaromatic steroid [MTAS]). The oil and biomarkers remaining in the treated soils followed similar second-order functions with increasing ultrasonication times. Biomarker elution was closely related to carbon numbers in the marker. For C26–34 17α 25-norhopanes, the smaller molecules were more readily eluted during 0–360s ultrasound. This trend was reversed upon application of ultrasound during 1080–1800s, with improved elution of larger molecules and elution followed a similar second-order function. For C26–28 TAS, smaller molecules were more readily eluted but the elution of larger molecules followed a similar second-order function. For C27–29 MTAS, elution of larger molecules was close to that of C26–34 17α 25-norhopanes. Results of SEM and XRD indicated that the mineral and chemical compositions of soils eluted at ultrasonication times of 1080–1800s closely resembled clean soils. [Copyright &y& Elsevier]

Abstract: An ultrasound-enhanced elution system employing water at a temperature of 70°C was used to remedy weathered soils contaminated with severely biodegraded heavy oil (SBHO). The effect of varying the ultrasonic irradiation time from 0 to 1800s on the elution of SBHO and three characteristic biomarkers (C26–34 17α 25-norhopanes, C26–28 TAS, and C27–29 MTAS) was analyzed using GC/MS, scanning electron microscopy (SEM), and X-ray diffraction (XRD). Elution of the three biomarkers was closely related to the carbon number of the marker. C26–34 17α 25-norhopanes and C26–28 TAS species with higher carbon numbers and C27–29 MTAS species with lower carbon numbers were more readily eluted using sonication times of 1080–1800s, while smaller TAS homologs were more readily eluted after sonication times of 0–360s. SEM images of samples treated for longer periods revealed larger “bare patches” on the soil surface. The results of XRD and energy spectroscopy experiments indicated that ultrasound irradiation for 1080s negatively affected the deposition of CaCO3, but overall improved the mineral and chemical compositions of treated soils and removal of SBHO. [Copyright &y& Elsevier]

Abstract: An ultrasound-enhanced elution system using water at a temperature of 70°C was employed to remove severely biodegraded heavy oil (SBHO) from weathered soil. The effect of varying the ultrasonic power density from 0 to 100WL−1 on the elution of SBHO and three characteristic biomarkers (C26–34 17α 25-norhopanes, C26–28 triaromatic steroids (TAS), and C27–29 methyl triaromatic steroids (MTAS) was analyzed using GC/MS, scanning electron microscopy (SEM), and X-ray diffraction (XRD). The amount of SBHO and biomarkers present in the treated soils and eluent had significant negative correlation with increasing ultrasonic power density. Elution of the three biomarkers was closely related to the number of C atoms in the marker: C26–34 17α 25-norhopanes with more carbon numbers and MTAS homologs with less carbon numbers were more readily eluted at higher power densities. The smaller TAS species were more readily eluted at a power density of less than 60WL−1, while larger TAS species displayed improved elution at power densities greater than 60WL−1. SEM images of samples treated at higher power densities revealed a more compact SBHO accumulation layer at the water–soil interface. The results of XRD and energy spectroscopy experiments indicated that ultrasound at a power density of 20WL−1 was helpful for the formation and sedimentation of calcite, although this effect disappeared at higher power of greater than 60WL−1. [Copyright &y& Elsevier]